The Association Between Alcohol Consumption and Lung Carcinoma by Histological Subtype

Abstract

Alcohol is a carcinogen suspected of increasing lung cancer risk. Therefore, we prospectively evaluated the relationship between alcohol consumption and lung carcinoma in 492,902 persons from the National Institutes of Health-AARP Diet and Health Study. We used Cox models to calculate hazard ratios and 95% confidence intervals, adjusting for tobacco smoking and other potential confounders. Between 1995/1996 and December 31, 2006, there were 10,227 incident cases of lung carcinoma, classified as adenocarcinoma (n = 4,036), squamous cell carcinoma (n = 1,998), small cell carcinoma (n = 1,524), undifferentiated carcinoma (n = 559), and other (n = 2,110). Compared with nondrinking, alcohol consumption was associated with a modest nonlinear reduction in total lung carcinoma risk at lower levels of consumption (for 0.5-<1 drink/day, HR = 0.89, 95% confidence interval: 0.82, 0.96) but a modest increase in risk in the highest category (for ≥7 drinks/day, HR = 1.11, 95% confidence interval: 1.00, 1.24). Regarding histological type, alcohol was associated with a nonlinear reduction in squamous cell carcinoma that became attenuated as consumption increased and a modest increase in adenocarcinoma among heavier drinkers. Cubic spline models confirmed these findings. Our data suggest that the relationship between alcohol consumption and lung carcinoma differs by histological subtype.

Keywords: alcohol consumption; cohort studies; lung cancer.

Figure 1.

Hazard ratios for the association between total alcohol consumption (drinks/day) and lung carcinoma in the National Institutes of Health-AARP Diet and Health Study, 1995/1996–2006. A) Total lung cancer; B) adenocarcinoma; C) squamous cell carcinoma. Estimates were obtained from restricted cubic spline models, and nondrinkers comprised the reference group in all analyses. Knot locations were derived from exposure percentiles (5th, 27.5th, 50th, 72.5th, and 95th percentile levels) and occurred at 0 drinks/day, 0.02 drinks/day, 0.13 drinks/day, 0.72 drinks/day, and 4.03 drinks/day, respectively. All models adjusted for sex, age at baseline, education, physical activity at work, leisure-time physical activity, energy intake (excluding alcohol; kcal/day), body mass index, race/ethnicity, Healthy Eating Index-2010 score (excluding alcohol), and tobacco smoking. The curves for all spline models were significant overall (P < 0.0001). Nonlinear associations were observed for total lung carcinoma (P for nonlinearity = 0.003) and squamous cell carcinoma (P for nonlinearity <0.001) but not for adenocarcinoma (P for nonlinearity = 0.694). Dashed lines, 95% confidence intervals.